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name: testing-strategy description: Generate tests following project conventions. Use when writing unit tests, integration tests, creating test fixtures, or implementing test builders. Triggers on requests like "write tests for", "add test coverage", "create test builder", "test this handler", or "implement tests".

Testing Strategy

Generate and maintain tests following project-specific conventions for this .NET/EF Core DDD codebase.

Quick Reference

Test Pyramid

Copy        +-------------+
        |  App Layer  |  Primary: Integration tests with SQLite in-memory
        |  Handlers   |  IAsyncLifetime pattern for isolation
        +-------------+
        |  Domain     |  Secondary: Unit tests for complex logic only
        |  Logic      |  Skip simple getters/setters
        +-------------+

Key Decisions

• NO E2E tests - Application layer integration tests provide sufficient coverage
• SQLite in-memory - Not EF Core InMemory provider (real constraints matter)
• IAsyncLifetime - Each test method gets fresh DB instance
• Builder pattern - Fluent builders with sensible defaults
• Japanese test names - Describe behavior clearly

Test Implementation Guide

Step 1: Determine Test Type

Step 2: Create Test Class

See references/patterns.md for complete templates:

• Application Layer: IAsyncLifetime pattern with SQLite
• Domain Layer: Simple unit test class

Step 3: Use Builders for Test Data

See references/builders.md for all available builders.

Key rules:

• Single entity: use defaults
• Multiple entities: MUST specify unique IDs

Step 4: Write Test Methods

See references/examples.md for common scenarios:

• CommandHandler tests
• QueryHandler with related data
• Domain state transitions
• Exception testing

Resources

Anti-Patterns Summary